Please vote for the Disney PBR material. Not convinced? Heres my 2 cents:4k & 8K PBR scans are coming. DDO / SubstancePainter and independents are churning them out. They come with a bunch of maps. The trend is inevitable, just like the touchscreen on our phones. Now, the maps come with AO, BUMP, DEPTH, GLOSS, HIGH GLOSS, NORMAL and ROUGHNESS. From the get-go you count more maps than you normally plug into Corona right? Here's is a free commercial use example in 4K:http://real-displacement-textures.com/

I am sure there is a round-about way to use the maps. But it probably differs from map to map, takes a lot of testing, with huge textures. Not ideal if you use a lot of them. What about METALNESS? Configuring assets in a game-asset-type of production pipeline and taking them into 3ds Max / Cinema 4D in 4K or 8K to use sweet sweet Corona for ArchiViz? Again you can fake it a little but...it's probably painful. The GGX was spot on by the way. But it is kind of the tip of the iceberg so-to-say. And I have no idea about coding but Disney PBR is certainly in top 3 hardest to implement. But it's the thing that also blows the competition out of the water.

Off Topic: Since I post once every 2 years, I would like to thank the guy who does the tutorials. That guy is simply the best. No other render software offered such an extensive view on how to be used. A million thanks.

Please vote for the Disney PBR material. Not convinced? Heres my 2 cents:4k & 8K PBR scans are coming. DDO / SubstancePainter and independents are churning them out. They come with a bunch of maps. The trend is inevitable, just like the touchscreen on our phones. Now, the maps come with AO, BUMP, DEPTH, GLOSS, HIGH GLOSS,

This.

How come more people vote for "presets" ? Are they aware they would be worthless since the material doesn't even work as it should. You can't get physically correct specular response without tinkering with IOR and Specular clamping (see Dubcat's guide) when having any glossy other than 1.0. Having straightforward artist-oriented materials would be biggest boon for 3D beginners, who could then be easily explained the principles in 5 minutes.